Darin Ruf of the Mets strikes out in the seventh inning...

Darin Ruf of the Mets strikes out in the seventh inning against the Nationals at Citi Field on Sept. 3. Credit: Jim McIsaac

ATLANTA — Darin Ruf, a strain on the Mets’ lineup for weeks, apparently now has a strain in his neck. 

The Mets put him on the injured list on Friday, the corresponding move to the promotion of top prospect Francisco Alvarez, and they hope the down time allows Ruf a chance to figure out whatever has been preventing him from being productive, injury or otherwise. 

Might the pain in his neck have caused some of his problems at the plate? 

“I hope that’s the case a little bit,” manager Buck Showalter said. “But I’ve had him in my office two or three times, seeing what might be going on, what he’s thinking. I think it’s good for him, too, kind of like [Eduardo Escobar], to clear the mechanism, so to speak. Just being able to take a step back and make use of that.” 

Since the Mets acquired him from the Giants at the trade deadline, Ruf has hit .152 with a .216 OBP and .197 slugging percentage. He has not homered. His struggles as the Mets’ primary DH against lefthanded pitchers was a reason the Mets called up Mark Vientos and now Alvarez. 

“It could be timing,” general manager Billy Eppler said. “It could be something material in his swing. It could be small sample. It could be a number of things. That’s up to us to uncover and that’s some of the questions we’re asking.” 

Hey there 

Dominic Smith, having completed a strong season with Triple-A Syracuse on Wednesday, is with the Mets this weekend on the taxi squad. He had a .299/.378/.518 slash line in the minors after his last demotion. 

Infielder Deven Marrero and righthander Stephen Nogosek also are physically with the club but not on the active roster. 

Extra bases 

Like Ruf, Starling Marte (fractured right middle finger) did not travel with the Mets for the road trip, Showalter said. He has been healing slower than they expected ... Mychal Givens (COVID IL) is scheduled to throw a simulated game on Saturday to “continue down the rehab path,” according to Showalter.